• 한국지반공학회:학술대회논문집
• /
• 한국지반공학회 2010년도 추계 학술발표회
• /
• pp.97-108
• /
• 2010

발포우레탄 패커를 이용한 압력식 쏘일네일링 공법은 기존 쏘일네일링 공법의 단점을 보완하기 위하여 개발되었으며, 그라우팅 두부에 패커를 설치하여 네일 정착부를 완전히 밀폐하고 압력 그라우팅을 실시하여 정착부의 유효직경 및 인발저항력을 증가시켜 안전율을 향상시키는 공법이다. 압력식 쏘일네일링 공법에 대한 효용성을 검증하기 위하여 발포우레탄 패커 특성시험 및 현장조건을 묘사한 실내 그라우팅 주입실험, 현장시험 및 FEM해석을 수행하였다. 본 공법의 필수요소인 발포우레탄 패커의 정착력 확인을 위한 패커 특성시험 결과, 공내에 작용하는 압력에 대하여 패커가 충분히 저항함을 알 수 있었으며, 인발저항력 증가 원인 분석을 위한 실내 및 현장 시험결과, 압력 그라우트에 의하여 그라우트의 품질확보, 보강력증가 및 주변지반의 압밀효과를 확인 하였다. 끝으로 압력식 쏘일네일링 공법을 적용한 사면 및 흙막이 벽체 설계/시공 사례를 분석하여 현장 적용시 본 공법의 효용성 및 대처능력의 우수함을 입증하였다.

• 한국암반공학회:학술대회논문집
• /
• 한국암반공학회 2001년도 추계공동학술발표회 논문집
• /
• pp.25-36
• /
• 2001

록볼트의 작용효과는 지반이 굴착되어 안정화되는 초기 1달간이 가장 중요하고 품질관리 문제는 지반조건에 따라 부식에 대한 문제가 있으나, 기존의 전면접착형 록볼트의 경우도 작업여건상 그 확실성은 떨어지는 것이 현실이다. 또한 작업이 시간소모가 크고, 볼트의 지지효과도 충진재가 고결되어야 발효되는 약점을 갖고 있어, 일본, 말레이시아, 유럽 등에서 전면 마찰형 즉시 지보기능이 가능한 Swellex Bolt를 영구지보재로 사용하고 있는 경향이 있다. 기존의 전면 접착형 SN Bolt(이형철근)로써 Grouting 몰탈볼트와 Cem Bolt로 설계된 장대·대단면 도로터널 지보재를 현대식 Swellex Bolt로 대체 설계변경이 가능한 것인지에 대하여 볼트의 지지력 시험(Pullout Test), 볼트재질의 내구성 연구 및 설계변경에 따른 수치해석 등을 실시하여, 볼트로써 지지력을 확인하고, 재질의 안전성을 조사한 후 시공 사이클 타임을 줄이며, 견고하고 시공성이 우수한 Swellex Bolt로의 설계변경을 제안하게 되었다.

• 한국건축시공학회:학술대회논문집
• /
• 한국건축시공학회 2011년도 춘계 학술논문 발표대회 2부
• /
• pp.89-90
• /
• 2011

External wall cleaning is a task that is currently being performed by human workers. The recent surge in the number of high-rise buildings has led to such problems as difficulties in cleaning the wall, high risk to the specialized workers, and increased maintenance expenses. As a fundamental measure to perform external wall cleaning work in a safer manner, automation/mechanization has been on the rise. This research aims to classify façade types and analyze the performance requirements of a wall-cleaning robot, as preliminary research to develop a wall-cleaning robot. The replacement of specialized workers with robots is expected to improve both safety for workers and quality of cleaning.

• 한국건축시공학회:학술대회논문집
• /
• 한국건축시공학회 2014년도 춘계 학술논문 발표대회
• /
• pp.170-171
• /
• 2014

The buildings constructed with steel structure is coated with certified fire resistive material to resist from fire. Coating materials lose their initial performances as time passes, so they need some maintenance. This study is covers standardization of the methods for assessing the durability of SFRM. In Korea, more than 90 percent of SFRM are used indoors. So This study is to decide proper test method through investigation and examination of effect factor to performance of fire-resistant structure and applicable test method.

• 한국건축시공학회:학술대회논문집
• /
• 한국건축시공학회 2014년도 춘계 학술논문 발표대회
• /
• pp.212-213
• /
• 2014

In case of fire spray protection sheath, fire resisting capacity is assessed for each material and installation method according to fire-resistive construction recognition. This study reviews effects of the percentage of water content that exist in fire spray protection sheath during the assess process of fire resisting capacity on fire resisting capacity, and changes of the percentage of water content according to temperature conditions. As a result of exams, as curing temperature is higher and thickness of specimen is thinner, decrease of the percentage of water content becomes significant.

• 한국지반공학회:학술대회논문집
• /
• 한국지반공학회 2006년도 춘계 학술발표회 논문집
• /
• pp.1155-1158
• /
• 2006

This paper presents a study on the construction condition and environmental effect of deep soil mixing. Construction condition means the difference in unconfined compressive strength with respect to the depth and location of samples. Environmental effect means alkalinity diffused from soil stabilizer. The experimental results indicate that the unconfined compressive strength vary with respect to the depth, and doesn't show consistency pattern. So, in field application we must decide a mixing ratio enough to satisfy the least unconfined compressive strength. The difference in unconfined compressive strength with respect to the location of samples is negligible. The generation of alkalinity from soil stabilizer is reduced by permeating in non-improved soil and it is expected that the diffusion of alkalinity has no environmental effect on soil and ground water.

• 한국건축시공학회:학술대회논문집
• /
• 한국건축시공학회 2011년도 추계 학술논문 발표대회
• /
• pp.169-170
• /
• 2011

In the connection of green frame, the bottom rebar of the precast concrete beam needs joint or anchorage to ensure structural integrity. However, given the characteristics of composite precast concrete joint, enough length over which rebar can be anchored or lap-spliced is not secured. In addition, due to issues with constructability, cost or quality, it is difficult to apply welding or mechanical connection techniques. Therefore, this study analyze the requirement for a bolt-type rebar coupler as a solution for the coupling issue between the lower rebars of green frame beam. The requirement for bolt-type rebar coupler proposed herein will provide basic data for development studies of the rebar coupler.

• 한국건축시공학회:학술대회논문집
• /
• 한국건축시공학회 2011년도 추계 학술논문 발표대회
• /
• pp.255-256
• /
• 2011

This study investigates the effect of a curing condition on the temperature history and strength development of concrete under -10℃. Combination of various curing methods was applied, i.e. a conventional form was combined with compressed insulation, heat panel and heat cable. Results showed that the concrete cured by a single use of a conventional form resulted in serious deterioration of early strength development. However, other concretes cured by the proposed curing methods maintained the temperature of the concretes between 5 and 20℃, and thus resulted in no frost damage.

• 한국건축시공학회:학술대회논문집
• /
• 한국건축시공학회 2011년도 추계 학술논문 발표대회
• /
• pp.107-108
• /
• 2011

The purpose of present study is to examine the application of effective curing to hardener-free epoxy-modified mortars. The epoxy-modified mortars are prepared with polymer-cement ratios, subjected to two types of curing conditions, and tested for compressive, flexural and tensile strengths. As a result, hardener-free epoxy-modified mortars with steam curing is markedly improved with increasing air-dry curing period. High strength development of the epoxy-modified mortars may be achieved by the dense microstructure by cement and the hardener of the epoxy resin in the mortars.

• 한국건축시공학회:학술대회논문집
• /
• 한국건축시공학회 2011년도 추계 학술논문 발표대회
• /
• pp.51-52
• /
• 2011

This study is to propose a curing method for a concrete wall structure under severe cold climate. The curing methods of using heated cable, heated panel and insulated form were applied. Results showed that the concrete cured by the heated cable resulted in the highest temperature history and the highest strength development at 28 days. Further, it is believed that the curing methods of the heated panel and insulated form are also recommendable for the resistance of the early frost damage on the concrete in practice.